1 /* SCTP kernel implementation 2 * (C) Copyright IBM Corp. 2001, 2004 3 * Copyright (c) 1999-2000 Cisco, Inc. 4 * Copyright (c) 1999-2001 Motorola, Inc. 5 * Copyright (c) 2001 Intel Corp. 6 * 7 * This file is part of the SCTP kernel implementation 8 * 9 * This SCTP implementation is free software; 10 * you can redistribute it and/or modify it under the terms of 11 * the GNU General Public License as published by 12 * the Free Software Foundation; either version 2, or (at your option) 13 * any later version. 14 * 15 * This SCTP implementation is distributed in the hope that it 16 * will be useful, but WITHOUT ANY WARRANTY; without even the implied 17 * ************************ 18 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 19 * See the GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with GNU CC; see the file COPYING. If not, see 23 * <http://www.gnu.org/licenses/>. 24 * 25 * Please send any bug reports or fixes you make to the 26 * email addresses: 27 * lksctp developers <linux-sctp@vger.kernel.org> 28 * 29 * Written or modified by: 30 * Randall Stewart <randall@sctp.chicago.il.us> 31 * Ken Morneau <kmorneau@cisco.com> 32 * Qiaobing Xie <qxie1@email.mot.com> 33 * La Monte H.P. Yarroll <piggy@acm.org> 34 * Karl Knutson <karl@athena.chicago.il.us> 35 * Jon Grimm <jgrimm@us.ibm.com> 36 * Xingang Guo <xingang.guo@intel.com> 37 * Hui Huang <hui.huang@nokia.com> 38 * Sridhar Samudrala <sri@us.ibm.com> 39 * Daisy Chang <daisyc@us.ibm.com> 40 * Dajiang Zhang <dajiang.zhang@nokia.com> 41 * Ardelle Fan <ardelle.fan@intel.com> 42 * Ryan Layer <rmlayer@us.ibm.com> 43 * Anup Pemmaiah <pemmaiah@cc.usu.edu> 44 * Kevin Gao <kevin.gao@intel.com> 45 */ 46 47 #ifndef __sctp_structs_h__ 48 #define __sctp_structs_h__ 49 50 #include <linux/ktime.h> 51 #include <linux/rhashtable.h> 52 #include <linux/socket.h> /* linux/in.h needs this!! */ 53 #include <linux/in.h> /* We get struct sockaddr_in. */ 54 #include <linux/in6.h> /* We get struct in6_addr */ 55 #include <linux/ipv6.h> 56 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */ 57 #include <linux/atomic.h> /* This gets us atomic counters. */ 58 #include <linux/skbuff.h> /* We need sk_buff_head. */ 59 #include <linux/workqueue.h> /* We need tq_struct. */ 60 #include <linux/sctp.h> /* We need sctp* header structs. */ 61 #include <net/sctp/auth.h> /* We need auth specific structs */ 62 #include <net/ip.h> /* For inet_skb_parm */ 63 64 /* A convenience structure for handling sockaddr structures. 65 * We should wean ourselves off this. 66 */ 67 union sctp_addr { 68 struct sockaddr_in v4; 69 struct sockaddr_in6 v6; 70 struct sockaddr sa; 71 }; 72 73 /* Forward declarations for data structures. */ 74 struct sctp_globals; 75 struct sctp_endpoint; 76 struct sctp_association; 77 struct sctp_transport; 78 struct sctp_packet; 79 struct sctp_chunk; 80 struct sctp_inq; 81 struct sctp_outq; 82 struct sctp_bind_addr; 83 struct sctp_ulpq; 84 struct sctp_ep_common; 85 struct crypto_shash; 86 struct sctp_stream; 87 88 89 #include <net/sctp/tsnmap.h> 90 #include <net/sctp/ulpevent.h> 91 #include <net/sctp/ulpqueue.h> 92 #include <net/sctp/stream_interleave.h> 93 94 /* Structures useful for managing bind/connect. */ 95 96 struct sctp_bind_bucket { 97 unsigned short port; 98 unsigned short fastreuse; 99 struct hlist_node node; 100 struct hlist_head owner; 101 struct net *net; 102 }; 103 104 struct sctp_bind_hashbucket { 105 spinlock_t lock; 106 struct hlist_head chain; 107 }; 108 109 /* Used for hashing all associations. */ 110 struct sctp_hashbucket { 111 rwlock_t lock; 112 struct hlist_head chain; 113 } __attribute__((__aligned__(8))); 114 115 116 /* The SCTP globals structure. */ 117 extern struct sctp_globals { 118 /* This is a list of groups of functions for each address 119 * family that we support. 120 */ 121 struct list_head address_families; 122 123 /* This is the hash of all endpoints. */ 124 struct sctp_hashbucket *ep_hashtable; 125 /* This is the sctp port control hash. */ 126 struct sctp_bind_hashbucket *port_hashtable; 127 /* This is the hash of all transports. */ 128 struct rhltable transport_hashtable; 129 130 /* Sizes of above hashtables. */ 131 int ep_hashsize; 132 int port_hashsize; 133 134 /* Default initialization values to be applied to new associations. */ 135 __u16 max_instreams; 136 __u16 max_outstreams; 137 138 /* Flag to indicate whether computing and verifying checksum 139 * is disabled. */ 140 bool checksum_disable; 141 } sctp_globals; 142 143 #define sctp_max_instreams (sctp_globals.max_instreams) 144 #define sctp_max_outstreams (sctp_globals.max_outstreams) 145 #define sctp_address_families (sctp_globals.address_families) 146 #define sctp_ep_hashsize (sctp_globals.ep_hashsize) 147 #define sctp_ep_hashtable (sctp_globals.ep_hashtable) 148 #define sctp_port_hashsize (sctp_globals.port_hashsize) 149 #define sctp_port_hashtable (sctp_globals.port_hashtable) 150 #define sctp_transport_hashtable (sctp_globals.transport_hashtable) 151 #define sctp_checksum_disable (sctp_globals.checksum_disable) 152 153 /* SCTP Socket type: UDP or TCP style. */ 154 enum sctp_socket_type { 155 SCTP_SOCKET_UDP = 0, 156 SCTP_SOCKET_UDP_HIGH_BANDWIDTH, 157 SCTP_SOCKET_TCP 158 }; 159 160 /* Per socket SCTP information. */ 161 struct sctp_sock { 162 /* inet_sock has to be the first member of sctp_sock */ 163 struct inet_sock inet; 164 /* What kind of a socket is this? */ 165 enum sctp_socket_type type; 166 167 /* PF_ family specific functions. */ 168 struct sctp_pf *pf; 169 170 /* Access to HMAC transform. */ 171 struct crypto_shash *hmac; 172 char *sctp_hmac_alg; 173 174 /* What is our base endpointer? */ 175 struct sctp_endpoint *ep; 176 177 struct sctp_bind_bucket *bind_hash; 178 /* Various Socket Options. */ 179 __u16 default_stream; 180 __u32 default_ppid; 181 __u16 default_flags; 182 __u32 default_context; 183 __u32 default_timetolive; 184 __u32 default_rcv_context; 185 int max_burst; 186 187 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 188 * the destination address every heartbeat interval. This value 189 * will be inherited by all new associations. 190 */ 191 __u32 hbinterval; 192 193 /* This is the max_retrans value for new associations. */ 194 __u16 pathmaxrxt; 195 196 /* The initial Path MTU to use for new associations. */ 197 __u32 pathmtu; 198 199 /* The default SACK delay timeout for new associations. */ 200 __u32 sackdelay; 201 __u32 sackfreq; 202 203 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 204 __u32 param_flags; 205 206 struct sctp_rtoinfo rtoinfo; 207 struct sctp_paddrparams paddrparam; 208 struct sctp_assocparams assocparams; 209 210 /* 211 * These two structures must be grouped together for the usercopy 212 * whitelist region. 213 */ 214 struct sctp_event_subscribe subscribe; 215 struct sctp_initmsg initmsg; 216 217 int user_frag; 218 219 __u32 autoclose; 220 __u32 adaptation_ind; 221 __u32 pd_point; 222 __u16 nodelay:1, 223 disable_fragments:1, 224 v4mapped:1, 225 frag_interleave:1, 226 strm_interleave:1, 227 recvrcvinfo:1, 228 recvnxtinfo:1, 229 data_ready_signalled:1; 230 231 atomic_t pd_mode; 232 /* Receive to here while partial delivery is in effect. */ 233 struct sk_buff_head pd_lobby; 234 235 /* These must be the last fields, as they will skipped on copies, 236 * like on accept and peeloff operations 237 */ 238 struct list_head auto_asconf_list; 239 int do_auto_asconf; 240 }; 241 242 static inline struct sctp_sock *sctp_sk(const struct sock *sk) 243 { 244 return (struct sctp_sock *)sk; 245 } 246 247 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 248 { 249 return (struct sock *)sp; 250 } 251 252 #if IS_ENABLED(CONFIG_IPV6) 253 struct sctp6_sock { 254 struct sctp_sock sctp; 255 struct ipv6_pinfo inet6; 256 }; 257 #endif /* CONFIG_IPV6 */ 258 259 260 /* This is our APPLICATION-SPECIFIC state cookie. 261 * THIS IS NOT DICTATED BY THE SPECIFICATION. 262 */ 263 /* These are the parts of an association which we send in the cookie. 264 * Most of these are straight out of: 265 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 266 * 267 */ 268 269 struct sctp_cookie { 270 271 /* My : Tag expected in every inbound packet and sent 272 * Verification: in the INIT or INIT ACK chunk. 273 * Tag : 274 */ 275 __u32 my_vtag; 276 277 /* Peer's : Tag expected in every outbound packet except 278 * Verification: in the INIT chunk. 279 * Tag : 280 */ 281 __u32 peer_vtag; 282 283 /* The rest of these are not from the spec, but really need to 284 * be in the cookie. 285 */ 286 287 /* My Tie Tag : Assist in discovering a restarting association. */ 288 __u32 my_ttag; 289 290 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 291 __u32 peer_ttag; 292 293 /* When does this cookie expire? */ 294 ktime_t expiration; 295 296 /* Number of inbound/outbound streams which are set 297 * and negotiated during the INIT process. 298 */ 299 __u16 sinit_num_ostreams; 300 __u16 sinit_max_instreams; 301 302 /* This is the first sequence number I used. */ 303 __u32 initial_tsn; 304 305 /* This holds the originating address of the INIT packet. */ 306 union sctp_addr peer_addr; 307 308 /* IG Section 2.35.3 309 * Include the source port of the INIT-ACK 310 */ 311 __u16 my_port; 312 313 __u8 prsctp_capable; 314 315 /* Padding for future use */ 316 __u8 padding; 317 318 __u32 adaptation_ind; 319 320 __u8 auth_random[sizeof(struct sctp_paramhdr) + 321 SCTP_AUTH_RANDOM_LENGTH]; 322 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 323 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 324 325 /* This is a shim for my peer's INIT packet, followed by 326 * a copy of the raw address list of the association. 327 * The length of the raw address list is saved in the 328 * raw_addr_list_len field, which will be used at the time when 329 * the association TCB is re-constructed from the cookie. 330 */ 331 __u32 raw_addr_list_len; 332 struct sctp_init_chunk peer_init[0]; 333 }; 334 335 336 /* The format of our cookie that we send to our peer. */ 337 struct sctp_signed_cookie { 338 __u8 signature[SCTP_SECRET_SIZE]; 339 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 340 struct sctp_cookie c; 341 } __packed; 342 343 /* This is another convenience type to allocate memory for address 344 * params for the maximum size and pass such structures around 345 * internally. 346 */ 347 union sctp_addr_param { 348 struct sctp_paramhdr p; 349 struct sctp_ipv4addr_param v4; 350 struct sctp_ipv6addr_param v6; 351 }; 352 353 /* A convenience type to allow walking through the various 354 * parameters and avoid casting all over the place. 355 */ 356 union sctp_params { 357 void *v; 358 struct sctp_paramhdr *p; 359 struct sctp_cookie_preserve_param *life; 360 struct sctp_hostname_param *dns; 361 struct sctp_cookie_param *cookie; 362 struct sctp_supported_addrs_param *sat; 363 struct sctp_ipv4addr_param *v4; 364 struct sctp_ipv6addr_param *v6; 365 union sctp_addr_param *addr; 366 struct sctp_adaptation_ind_param *aind; 367 struct sctp_supported_ext_param *ext; 368 struct sctp_random_param *random; 369 struct sctp_chunks_param *chunks; 370 struct sctp_hmac_algo_param *hmac_algo; 371 struct sctp_addip_param *addip; 372 }; 373 374 /* RFC 2960. Section 3.3.5 Heartbeat. 375 * Heartbeat Information: variable length 376 * The Sender-specific Heartbeat Info field should normally include 377 * information about the sender's current time when this HEARTBEAT 378 * chunk is sent and the destination transport address to which this 379 * HEARTBEAT is sent (see Section 8.3). 380 */ 381 struct sctp_sender_hb_info { 382 struct sctp_paramhdr param_hdr; 383 union sctp_addr daddr; 384 unsigned long sent_at; 385 __u64 hb_nonce; 386 }; 387 388 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 389 gfp_t gfp); 390 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 391 void sctp_stream_free(struct sctp_stream *stream); 392 void sctp_stream_clear(struct sctp_stream *stream); 393 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 394 395 /* What is the current SSN number for this stream? */ 396 #define sctp_ssn_peek(stream, type, sid) \ 397 ((stream)->type[sid].ssn) 398 399 /* Return the next SSN number for this stream. */ 400 #define sctp_ssn_next(stream, type, sid) \ 401 ((stream)->type[sid].ssn++) 402 403 /* Skip over this ssn and all below. */ 404 #define sctp_ssn_skip(stream, type, sid, ssn) \ 405 ((stream)->type[sid].ssn = ssn + 1) 406 407 /* What is the current MID number for this stream? */ 408 #define sctp_mid_peek(stream, type, sid) \ 409 ((stream)->type[sid].mid) 410 411 /* Return the next MID number for this stream. */ 412 #define sctp_mid_next(stream, type, sid) \ 413 ((stream)->type[sid].mid++) 414 415 /* Skip over this mid and all below. */ 416 #define sctp_mid_skip(stream, type, sid, mid) \ 417 ((stream)->type[sid].mid = mid + 1) 418 419 #define sctp_stream_in(asoc, sid) (&(asoc)->stream.in[sid]) 420 421 /* What is the current MID_uo number for this stream? */ 422 #define sctp_mid_uo_peek(stream, type, sid) \ 423 ((stream)->type[sid].mid_uo) 424 425 /* Return the next MID_uo number for this stream. */ 426 #define sctp_mid_uo_next(stream, type, sid) \ 427 ((stream)->type[sid].mid_uo++) 428 429 /* 430 * Pointers to address related SCTP functions. 431 * (i.e. things that depend on the address family.) 432 */ 433 struct sctp_af { 434 int (*sctp_xmit) (struct sk_buff *skb, 435 struct sctp_transport *); 436 int (*setsockopt) (struct sock *sk, 437 int level, 438 int optname, 439 char __user *optval, 440 unsigned int optlen); 441 int (*getsockopt) (struct sock *sk, 442 int level, 443 int optname, 444 char __user *optval, 445 int __user *optlen); 446 int (*compat_setsockopt) (struct sock *sk, 447 int level, 448 int optname, 449 char __user *optval, 450 unsigned int optlen); 451 int (*compat_getsockopt) (struct sock *sk, 452 int level, 453 int optname, 454 char __user *optval, 455 int __user *optlen); 456 void (*get_dst) (struct sctp_transport *t, 457 union sctp_addr *saddr, 458 struct flowi *fl, 459 struct sock *sk); 460 void (*get_saddr) (struct sctp_sock *sk, 461 struct sctp_transport *t, 462 struct flowi *fl); 463 void (*copy_addrlist) (struct list_head *, 464 struct net_device *); 465 int (*cmp_addr) (const union sctp_addr *addr1, 466 const union sctp_addr *addr2); 467 void (*addr_copy) (union sctp_addr *dst, 468 union sctp_addr *src); 469 void (*from_skb) (union sctp_addr *, 470 struct sk_buff *skb, 471 int saddr); 472 void (*from_sk) (union sctp_addr *, 473 struct sock *sk); 474 void (*from_addr_param) (union sctp_addr *, 475 union sctp_addr_param *, 476 __be16 port, int iif); 477 int (*to_addr_param) (const union sctp_addr *, 478 union sctp_addr_param *); 479 int (*addr_valid) (union sctp_addr *, 480 struct sctp_sock *, 481 const struct sk_buff *); 482 enum sctp_scope (*scope)(union sctp_addr *); 483 void (*inaddr_any) (union sctp_addr *, __be16); 484 int (*is_any) (const union sctp_addr *); 485 int (*available) (union sctp_addr *, 486 struct sctp_sock *); 487 int (*skb_iif) (const struct sk_buff *sk); 488 int (*is_ce) (const struct sk_buff *sk); 489 void (*seq_dump_addr)(struct seq_file *seq, 490 union sctp_addr *addr); 491 void (*ecn_capable)(struct sock *sk); 492 __u16 net_header_len; 493 int sockaddr_len; 494 int (*ip_options_len)(struct sock *sk); 495 sa_family_t sa_family; 496 struct list_head list; 497 }; 498 499 struct sctp_af *sctp_get_af_specific(sa_family_t); 500 int sctp_register_af(struct sctp_af *); 501 502 /* Protocol family functions. */ 503 struct sctp_pf { 504 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 505 void (*skb_msgname) (struct sk_buff *, char *, int *); 506 int (*af_supported) (sa_family_t, struct sctp_sock *); 507 int (*cmp_addr) (const union sctp_addr *, 508 const union sctp_addr *, 509 struct sctp_sock *); 510 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 511 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 512 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 513 struct sock *(*create_accept_sk) (struct sock *sk, 514 struct sctp_association *asoc, 515 bool kern); 516 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 517 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 518 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 519 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 520 struct sctp_af *af; 521 }; 522 523 524 /* Structure to track chunk fragments that have been acked, but peer 525 * fragments of the same message have not. 526 */ 527 struct sctp_datamsg { 528 /* Chunks waiting to be submitted to lower layer. */ 529 struct list_head chunks; 530 /* Reference counting. */ 531 refcount_t refcnt; 532 /* When is this message no longer interesting to the peer? */ 533 unsigned long expires_at; 534 /* Did the messenge fail to send? */ 535 int send_error; 536 u8 send_failed:1, 537 can_delay:1, /* should this message be Nagle delayed */ 538 abandoned:1; /* should this message be abandoned */ 539 }; 540 541 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 542 struct sctp_sndrcvinfo *, 543 struct iov_iter *); 544 void sctp_datamsg_free(struct sctp_datamsg *); 545 void sctp_datamsg_put(struct sctp_datamsg *); 546 void sctp_chunk_fail(struct sctp_chunk *, int error); 547 int sctp_chunk_abandoned(struct sctp_chunk *); 548 549 /* RFC2960 1.4 Key Terms 550 * 551 * o Chunk: A unit of information within an SCTP packet, consisting of 552 * a chunk header and chunk-specific content. 553 * 554 * As a matter of convenience, we remember the SCTP common header for 555 * each chunk as well as a few other header pointers... 556 */ 557 struct sctp_chunk { 558 struct list_head list; 559 560 refcount_t refcnt; 561 562 /* How many times this chunk have been sent, for prsctp RTX policy */ 563 int sent_count; 564 565 union { 566 /* This is our link to the per-transport transmitted list. */ 567 struct list_head transmitted_list; 568 /* List in specific stream outq */ 569 struct list_head stream_list; 570 }; 571 572 /* This field is used by chunks that hold fragmented data. 573 * For the first fragment this is the list that holds the rest of 574 * fragments. For the remaining fragments, this is the link to the 575 * frag_list maintained in the first fragment. 576 */ 577 struct list_head frag_list; 578 579 /* This points to the sk_buff containing the actual data. */ 580 struct sk_buff *skb; 581 582 union { 583 /* In case of GSO packets, this will store the head one */ 584 struct sk_buff *head_skb; 585 /* In case of auth enabled, this will point to the shkey */ 586 struct sctp_shared_key *shkey; 587 }; 588 589 /* These are the SCTP headers by reverse order in a packet. 590 * Note that some of these may happen more than once. In that 591 * case, we point at the "current" one, whatever that means 592 * for that level of header. 593 */ 594 595 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 596 union sctp_params param_hdr; 597 union { 598 __u8 *v; 599 struct sctp_datahdr *data_hdr; 600 struct sctp_inithdr *init_hdr; 601 struct sctp_sackhdr *sack_hdr; 602 struct sctp_heartbeathdr *hb_hdr; 603 struct sctp_sender_hb_info *hbs_hdr; 604 struct sctp_shutdownhdr *shutdown_hdr; 605 struct sctp_signed_cookie *cookie_hdr; 606 struct sctp_ecnehdr *ecne_hdr; 607 struct sctp_cwrhdr *ecn_cwr_hdr; 608 struct sctp_errhdr *err_hdr; 609 struct sctp_addiphdr *addip_hdr; 610 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 611 struct sctp_authhdr *auth_hdr; 612 struct sctp_idatahdr *idata_hdr; 613 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 614 } subh; 615 616 __u8 *chunk_end; 617 618 struct sctp_chunkhdr *chunk_hdr; 619 struct sctphdr *sctp_hdr; 620 621 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 622 struct sctp_sndrcvinfo sinfo; 623 624 /* Which association does this belong to? */ 625 struct sctp_association *asoc; 626 627 /* What endpoint received this chunk? */ 628 struct sctp_ep_common *rcvr; 629 630 /* We fill this in if we are calculating RTT. */ 631 unsigned long sent_at; 632 633 /* What is the origin IP address for this chunk? */ 634 union sctp_addr source; 635 /* Destination address for this chunk. */ 636 union sctp_addr dest; 637 638 /* For outbound message, track all fragments for SEND_FAILED. */ 639 struct sctp_datamsg *msg; 640 641 /* For an inbound chunk, this tells us where it came from. 642 * For an outbound chunk, it tells us where we'd like it to 643 * go. It is NULL if we have no preference. 644 */ 645 struct sctp_transport *transport; 646 647 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 648 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 649 * spec violates the principle premis that all chunks are processed 650 * in order. 651 */ 652 struct sk_buff *auth_chunk; 653 654 #define SCTP_CAN_FRTX 0x0 655 #define SCTP_NEED_FRTX 0x1 656 #define SCTP_DONT_FRTX 0x2 657 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 658 has_tsn:1, /* Does this chunk have a TSN yet? */ 659 has_ssn:1, /* Does this chunk have a SSN yet? */ 660 #define has_mid has_ssn 661 singleton:1, /* Only chunk in the packet? */ 662 end_of_packet:1, /* Last chunk in the packet? */ 663 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 664 pdiscard:1, /* Discard the whole packet now? */ 665 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 666 data_accepted:1, /* At least 1 chunk accepted */ 667 auth:1, /* IN: was auth'ed | OUT: needs auth */ 668 has_asconf:1, /* IN: have seen an asconf before */ 669 tsn_missing_report:2, /* Data chunk missing counter. */ 670 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 671 }; 672 673 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 674 void sctp_chunk_hold(struct sctp_chunk *); 675 void sctp_chunk_put(struct sctp_chunk *); 676 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 677 struct iov_iter *from); 678 void sctp_chunk_free(struct sctp_chunk *); 679 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 680 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 681 const struct sctp_association *, 682 struct sock *, gfp_t gfp); 683 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 684 union sctp_addr *); 685 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 686 687 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 688 { 689 return ntohs(ch->subh.data_hdr->stream); 690 } 691 692 enum { 693 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 694 SCTP_ADDR_SRC, /* address can be used as source */ 695 SCTP_ADDR_DEL, /* address about to be deleted */ 696 }; 697 698 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 699 struct sctp_sockaddr_entry { 700 struct list_head list; 701 struct rcu_head rcu; 702 union sctp_addr a; 703 __u8 state; 704 __u8 valid; 705 }; 706 707 #define SCTP_ADDRESS_TICK_DELAY 500 708 709 /* This structure holds lists of chunks as we are assembling for 710 * transmission. 711 */ 712 struct sctp_packet { 713 /* These are the SCTP header values (host order) for the packet. */ 714 __u16 source_port; 715 __u16 destination_port; 716 __u32 vtag; 717 718 /* This contains the payload chunks. */ 719 struct list_head chunk_list; 720 721 /* This is the overhead of the sctp and ip headers. */ 722 size_t overhead; 723 /* This is the total size of all chunks INCLUDING padding. */ 724 size_t size; 725 /* This is the maximum size this packet may have */ 726 size_t max_size; 727 728 /* The packet is destined for this transport address. 729 * The function we finally use to pass down to the next lower 730 * layer lives in the transport structure. 731 */ 732 struct sctp_transport *transport; 733 734 /* pointer to the auth chunk for this packet */ 735 struct sctp_chunk *auth; 736 737 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 738 has_sack:1, /* This packet contains a SACK chunk. */ 739 has_auth:1, /* This packet contains an AUTH chunk */ 740 has_data:1, /* This packet contains at least 1 DATA chunk */ 741 ipfragok:1; /* So let ip fragment this packet */ 742 }; 743 744 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 745 __u16 sport, __u16 dport); 746 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 747 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 748 struct sctp_chunk *chunk, 749 int one_packet, gfp_t gfp); 750 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 751 struct sctp_chunk *chunk); 752 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 753 void sctp_packet_free(struct sctp_packet *); 754 755 static inline int sctp_packet_empty(struct sctp_packet *packet) 756 { 757 return packet->size == packet->overhead; 758 } 759 760 /* This represents a remote transport address. 761 * For local transport addresses, we just use union sctp_addr. 762 * 763 * RFC2960 Section 1.4 Key Terms 764 * 765 * o Transport address: A Transport Address is traditionally defined 766 * by Network Layer address, Transport Layer protocol and Transport 767 * Layer port number. In the case of SCTP running over IP, a 768 * transport address is defined by the combination of an IP address 769 * and an SCTP port number (where SCTP is the Transport protocol). 770 * 771 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 772 * 773 * o The sender keeps a separate congestion control parameter set for 774 * each of the destination addresses it can send to (not each 775 * source-destination pair but for each destination). The parameters 776 * should decay if the address is not used for a long enough time 777 * period. 778 * 779 */ 780 struct sctp_transport { 781 /* A list of transports. */ 782 struct list_head transports; 783 struct rhlist_head node; 784 785 /* Reference counting. */ 786 refcount_t refcnt; 787 /* RTO-Pending : A flag used to track if one of the DATA 788 * chunks sent to this address is currently being 789 * used to compute a RTT. If this flag is 0, 790 * the next DATA chunk sent to this destination 791 * should be used to compute a RTT and this flag 792 * should be set. Every time the RTT 793 * calculation completes (i.e. the DATA chunk 794 * is SACK'd) clear this flag. 795 */ 796 __u32 rto_pending:1, 797 798 /* 799 * hb_sent : a flag that signals that we have a pending 800 * heartbeat. 801 */ 802 hb_sent:1, 803 804 /* Is the Path MTU update pending on this tranport */ 805 pmtu_pending:1, 806 807 dst_pending_confirm:1, /* need to confirm neighbour */ 808 809 /* Has this transport moved the ctsn since we last sacked */ 810 sack_generation:1; 811 u32 dst_cookie; 812 813 struct flowi fl; 814 815 /* This is the peer's IP address and port. */ 816 union sctp_addr ipaddr; 817 818 /* These are the functions we call to handle LLP stuff. */ 819 struct sctp_af *af_specific; 820 821 /* Which association do we belong to? */ 822 struct sctp_association *asoc; 823 824 /* RFC2960 825 * 826 * 12.3 Per Transport Address Data 827 * 828 * For each destination transport address in the peer's 829 * address list derived from the INIT or INIT ACK chunk, a 830 * number of data elements needs to be maintained including: 831 */ 832 /* RTO : The current retransmission timeout value. */ 833 unsigned long rto; 834 835 __u32 rtt; /* This is the most recent RTT. */ 836 837 /* RTTVAR : The current RTT variation. */ 838 __u32 rttvar; 839 840 /* SRTT : The current smoothed round trip time. */ 841 __u32 srtt; 842 843 /* 844 * These are the congestion stats. 845 */ 846 /* cwnd : The current congestion window. */ 847 __u32 cwnd; /* This is the actual cwnd. */ 848 849 /* ssthresh : The current slow start threshold value. */ 850 __u32 ssthresh; 851 852 /* partial : The tracking method for increase of cwnd when in 853 * bytes acked : congestion avoidance mode (see Section 6.2.2) 854 */ 855 __u32 partial_bytes_acked; 856 857 /* Data that has been sent, but not acknowledged. */ 858 __u32 flight_size; 859 860 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 861 862 /* Destination */ 863 struct dst_entry *dst; 864 /* Source address. */ 865 union sctp_addr saddr; 866 867 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 868 * the destination address every heartbeat interval. 869 */ 870 unsigned long hbinterval; 871 872 /* SACK delay timeout */ 873 unsigned long sackdelay; 874 __u32 sackfreq; 875 876 /* When was the last time that we heard from this transport? We use 877 * this to pick new active and retran paths. 878 */ 879 ktime_t last_time_heard; 880 881 /* When was the last time that we sent a chunk using this 882 * transport? We use this to check for idle transports 883 */ 884 unsigned long last_time_sent; 885 886 /* Last time(in jiffies) when cwnd is reduced due to the congestion 887 * indication based on ECNE chunk. 888 */ 889 unsigned long last_time_ecne_reduced; 890 891 /* This is the max_retrans value for the transport and will 892 * be initialized from the assocs value. This can be changed 893 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 894 */ 895 __u16 pathmaxrxt; 896 897 /* This is the partially failed retrans value for the transport 898 * and will be initialized from the assocs value. This can be changed 899 * using the SCTP_PEER_ADDR_THLDS socket option 900 */ 901 int pf_retrans; 902 /* PMTU : The current known path MTU. */ 903 __u32 pathmtu; 904 905 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 906 __u32 param_flags; 907 908 /* The number of times INIT has been sent on this transport. */ 909 int init_sent_count; 910 911 /* state : The current state of this destination, 912 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 913 */ 914 int state; 915 916 /* These are the error stats for this destination. */ 917 918 /* Error count : The current error count for this destination. */ 919 unsigned short error_count; 920 921 /* Per : A timer used by each destination. 922 * Destination : 923 * Timer : 924 * 925 * [Everywhere else in the text this is called T3-rtx. -ed] 926 */ 927 struct timer_list T3_rtx_timer; 928 929 /* Heartbeat timer is per destination. */ 930 struct timer_list hb_timer; 931 932 /* Timer to handle ICMP proto unreachable envets */ 933 struct timer_list proto_unreach_timer; 934 935 /* Timer to handler reconf chunk rtx */ 936 struct timer_list reconf_timer; 937 938 /* Since we're using per-destination retransmission timers 939 * (see above), we're also using per-destination "transmitted" 940 * queues. This probably ought to be a private struct 941 * accessible only within the outqueue, but it's not, yet. 942 */ 943 struct list_head transmitted; 944 945 /* We build bundle-able packets for this transport here. */ 946 struct sctp_packet packet; 947 948 /* This is the list of transports that have chunks to send. */ 949 struct list_head send_ready; 950 951 /* State information saved for SFR_CACC algorithm. The key 952 * idea in SFR_CACC is to maintain state at the sender on a 953 * per-destination basis when a changeover happens. 954 * char changeover_active; 955 * char cycling_changeover; 956 * __u32 next_tsn_at_change; 957 * char cacc_saw_newack; 958 */ 959 struct { 960 /* An unsigned integer, which stores the next TSN to be 961 * used by the sender, at the moment of changeover. 962 */ 963 __u32 next_tsn_at_change; 964 965 /* A flag which indicates the occurrence of a changeover */ 966 char changeover_active; 967 968 /* A flag which indicates whether the change of primary is 969 * the first switch to this destination address during an 970 * active switch. 971 */ 972 char cycling_changeover; 973 974 /* A temporary flag, which is used during the processing of 975 * a SACK to estimate the causative TSN(s)'s group. 976 */ 977 char cacc_saw_newack; 978 } cacc; 979 980 /* 64-bit random number sent with heartbeat. */ 981 __u64 hb_nonce; 982 983 struct rcu_head rcu; 984 }; 985 986 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 987 gfp_t); 988 void sctp_transport_set_owner(struct sctp_transport *, 989 struct sctp_association *); 990 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 991 struct sctp_sock *); 992 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 993 void sctp_transport_free(struct sctp_transport *); 994 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 995 void sctp_transport_reset_hb_timer(struct sctp_transport *); 996 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 997 int sctp_transport_hold(struct sctp_transport *); 998 void sctp_transport_put(struct sctp_transport *); 999 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1000 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1001 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1002 enum sctp_lower_cwnd reason); 1003 void sctp_transport_burst_limited(struct sctp_transport *); 1004 void sctp_transport_burst_reset(struct sctp_transport *); 1005 unsigned long sctp_transport_timeout(struct sctp_transport *); 1006 void sctp_transport_reset(struct sctp_transport *t); 1007 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1008 void sctp_transport_immediate_rtx(struct sctp_transport *); 1009 void sctp_transport_dst_release(struct sctp_transport *t); 1010 void sctp_transport_dst_confirm(struct sctp_transport *t); 1011 1012 1013 /* This is the structure we use to queue packets as they come into 1014 * SCTP. We write packets to it and read chunks from it. 1015 */ 1016 struct sctp_inq { 1017 /* This is actually a queue of sctp_chunk each 1018 * containing a partially decoded packet. 1019 */ 1020 struct list_head in_chunk_list; 1021 /* This is the packet which is currently off the in queue and is 1022 * being worked on through the inbound chunk processing. 1023 */ 1024 struct sctp_chunk *in_progress; 1025 1026 /* This is the delayed task to finish delivering inbound 1027 * messages. 1028 */ 1029 struct work_struct immediate; 1030 }; 1031 1032 void sctp_inq_init(struct sctp_inq *); 1033 void sctp_inq_free(struct sctp_inq *); 1034 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1035 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1036 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1037 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1038 1039 /* This is the structure we use to hold outbound chunks. You push 1040 * chunks in and they automatically pop out the other end as bundled 1041 * packets (it calls (*output_handler)()). 1042 * 1043 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1044 * and 8.2 of the v13 draft. 1045 * 1046 * It handles retransmissions. The connection to the timeout portion 1047 * of the state machine is through sctp_..._timeout() and timeout_handler. 1048 * 1049 * If you feed it SACKs, it will eat them. 1050 * 1051 * If you give it big chunks, it will fragment them. 1052 * 1053 * It assigns TSN's to data chunks. This happens at the last possible 1054 * instant before transmission. 1055 * 1056 * When free()'d, it empties itself out via output_handler(). 1057 */ 1058 struct sctp_outq { 1059 struct sctp_association *asoc; 1060 1061 /* Data pending that has never been transmitted. */ 1062 struct list_head out_chunk_list; 1063 1064 /* Stream scheduler being used */ 1065 struct sctp_sched_ops *sched; 1066 1067 unsigned int out_qlen; /* Total length of queued data chunks. */ 1068 1069 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1070 unsigned int error; 1071 1072 /* These are control chunks we want to send. */ 1073 struct list_head control_chunk_list; 1074 1075 /* These are chunks that have been sacked but are above the 1076 * CTSN, or cumulative tsn ack point. 1077 */ 1078 struct list_head sacked; 1079 1080 /* Put chunks on this list to schedule them for 1081 * retransmission. 1082 */ 1083 struct list_head retransmit; 1084 1085 /* Put chunks on this list to save them for FWD TSN processing as 1086 * they were abandoned. 1087 */ 1088 struct list_head abandoned; 1089 1090 /* How many unackd bytes do we have in-flight? */ 1091 __u32 outstanding_bytes; 1092 1093 /* Are we doing fast-rtx on this queue */ 1094 char fast_rtx; 1095 1096 /* Corked? */ 1097 char cork; 1098 }; 1099 1100 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1101 void sctp_outq_teardown(struct sctp_outq *); 1102 void sctp_outq_free(struct sctp_outq*); 1103 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1104 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1105 int sctp_outq_is_empty(const struct sctp_outq *); 1106 void sctp_outq_restart(struct sctp_outq *); 1107 1108 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1109 enum sctp_retransmit_reason reason); 1110 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1111 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1112 void sctp_prsctp_prune(struct sctp_association *asoc, 1113 struct sctp_sndrcvinfo *sinfo, int msg_len); 1114 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1115 /* Uncork and flush an outqueue. */ 1116 static inline void sctp_outq_cork(struct sctp_outq *q) 1117 { 1118 q->cork = 1; 1119 } 1120 1121 /* SCTP skb control block. 1122 * sctp_input_cb is currently used on rx and sock rx queue 1123 */ 1124 struct sctp_input_cb { 1125 union { 1126 struct inet_skb_parm h4; 1127 #if IS_ENABLED(CONFIG_IPV6) 1128 struct inet6_skb_parm h6; 1129 #endif 1130 } header; 1131 struct sctp_chunk *chunk; 1132 struct sctp_af *af; 1133 }; 1134 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1135 1136 struct sctp_output_cb { 1137 struct sk_buff *last; 1138 }; 1139 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1140 1141 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1142 { 1143 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1144 1145 return chunk->head_skb ? : skb; 1146 } 1147 1148 /* These bind address data fields common between endpoints and associations */ 1149 struct sctp_bind_addr { 1150 1151 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1152 * 1153 * SCTP Port: The local SCTP port number the endpoint is 1154 * bound to. 1155 */ 1156 __u16 port; 1157 1158 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1159 * 1160 * Address List: The list of IP addresses that this instance 1161 * has bound. This information is passed to one's 1162 * peer(s) in INIT and INIT ACK chunks. 1163 */ 1164 struct list_head address_list; 1165 }; 1166 1167 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1168 void sctp_bind_addr_free(struct sctp_bind_addr *); 1169 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1170 const struct sctp_bind_addr *src, 1171 enum sctp_scope scope, gfp_t gfp, 1172 int flags); 1173 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1174 const struct sctp_bind_addr *src, 1175 gfp_t gfp); 1176 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1177 int new_size, __u8 addr_state, gfp_t gfp); 1178 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1179 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1180 struct sctp_sock *); 1181 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1182 struct sctp_sock *, struct sctp_sock *); 1183 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1184 const union sctp_addr *addr); 1185 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1186 const union sctp_addr *addrs, 1187 int addrcnt, 1188 struct sctp_sock *opt); 1189 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1190 int *addrs_len, 1191 gfp_t gfp); 1192 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1193 __u16 port, gfp_t gfp); 1194 1195 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1196 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1197 const enum sctp_scope scope); 1198 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1199 int sctp_is_ep_boundall(struct sock *sk); 1200 1201 1202 /* What type of endpoint? */ 1203 enum sctp_endpoint_type { 1204 SCTP_EP_TYPE_SOCKET, 1205 SCTP_EP_TYPE_ASSOCIATION, 1206 }; 1207 1208 /* 1209 * A common base class to bridge the implmentation view of a 1210 * socket (usually listening) endpoint versus an association's 1211 * local endpoint. 1212 * This common structure is useful for several purposes: 1213 * 1) Common interface for lookup routines. 1214 * a) Subfunctions work for either endpoint or association 1215 * b) Single interface to lookup allows hiding the lookup lock rather 1216 * than acquiring it externally. 1217 * 2) Common interface for the inbound chunk handling/state machine. 1218 * 3) Common object handling routines for reference counting, etc. 1219 * 4) Disentangle association lookup from endpoint lookup, where we 1220 * do not have to find our endpoint to find our association. 1221 * 1222 */ 1223 1224 struct sctp_ep_common { 1225 /* Fields to help us manage our entries in the hash tables. */ 1226 struct hlist_node node; 1227 int hashent; 1228 1229 /* Runtime type information. What kind of endpoint is this? */ 1230 enum sctp_endpoint_type type; 1231 1232 /* Some fields to help us manage this object. 1233 * refcnt - Reference count access to this object. 1234 * dead - Do not attempt to use this object. 1235 */ 1236 refcount_t refcnt; 1237 bool dead; 1238 1239 /* What socket does this endpoint belong to? */ 1240 struct sock *sk; 1241 1242 /* This is where we receive inbound chunks. */ 1243 struct sctp_inq inqueue; 1244 1245 /* This substructure includes the defining parameters of the 1246 * endpoint: 1247 * bind_addr.port is our shared port number. 1248 * bind_addr.address_list is our set of local IP addresses. 1249 */ 1250 struct sctp_bind_addr bind_addr; 1251 }; 1252 1253 1254 /* RFC Section 1.4 Key Terms 1255 * 1256 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1257 * multi-homed host, an SCTP endpoint is represented to its peers as a 1258 * combination of a set of eligible destination transport addresses to 1259 * which SCTP packets can be sent and a set of eligible source 1260 * transport addresses from which SCTP packets can be received. 1261 * All transport addresses used by an SCTP endpoint must use the 1262 * same port number, but can use multiple IP addresses. A transport 1263 * address used by an SCTP endpoint must not be used by another 1264 * SCTP endpoint. In other words, a transport address is unique 1265 * to an SCTP endpoint. 1266 * 1267 * From an implementation perspective, each socket has one of these. 1268 * A TCP-style socket will have exactly one association on one of 1269 * these. An UDP-style socket will have multiple associations hanging 1270 * off one of these. 1271 */ 1272 1273 struct sctp_endpoint { 1274 /* Common substructure for endpoint and association. */ 1275 struct sctp_ep_common base; 1276 1277 /* Associations: A list of current associations and mappings 1278 * to the data consumers for each association. This 1279 * may be in the form of a hash table or other 1280 * implementation dependent structure. The data 1281 * consumers may be process identification 1282 * information such as file descriptors, named pipe 1283 * pointer, or table pointers dependent on how SCTP 1284 * is implemented. 1285 */ 1286 /* This is really a list of struct sctp_association entries. */ 1287 struct list_head asocs; 1288 1289 /* Secret Key: A secret key used by this endpoint to compute 1290 * the MAC. This SHOULD be a cryptographic quality 1291 * random number with a sufficient length. 1292 * Discussion in [RFC1750] can be helpful in 1293 * selection of the key. 1294 */ 1295 __u8 secret_key[SCTP_SECRET_SIZE]; 1296 1297 /* digest: This is a digest of the sctp cookie. This field is 1298 * only used on the receive path when we try to validate 1299 * that the cookie has not been tampered with. We put 1300 * this here so we pre-allocate this once and can re-use 1301 * on every receive. 1302 */ 1303 __u8 *digest; 1304 1305 /* sendbuf acct. policy. */ 1306 __u32 sndbuf_policy; 1307 1308 /* rcvbuf acct. policy. */ 1309 __u32 rcvbuf_policy; 1310 1311 /* SCTP AUTH: array of the HMACs that will be allocated 1312 * we need this per association so that we don't serialize 1313 */ 1314 struct crypto_shash **auth_hmacs; 1315 1316 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1317 struct sctp_hmac_algo_param *auth_hmacs_list; 1318 1319 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1320 struct sctp_chunks_param *auth_chunk_list; 1321 1322 /* SCTP-AUTH: endpoint shared keys */ 1323 struct list_head endpoint_shared_keys; 1324 __u16 active_key_id; 1325 __u8 auth_enable:1, 1326 prsctp_enable:1, 1327 reconf_enable:1; 1328 1329 __u8 strreset_enable; 1330 1331 /* Security identifiers from incoming (INIT). These are set by 1332 * security_sctp_assoc_request(). These will only be used by 1333 * SCTP TCP type sockets and peeled off connections as they 1334 * cause a new socket to be generated. security_sctp_sk_clone() 1335 * will then plug these into the new socket. 1336 */ 1337 1338 u32 secid; 1339 u32 peer_secid; 1340 }; 1341 1342 /* Recover the outter endpoint structure. */ 1343 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1344 { 1345 struct sctp_endpoint *ep; 1346 1347 ep = container_of(base, struct sctp_endpoint, base); 1348 return ep; 1349 } 1350 1351 /* These are function signatures for manipulating endpoints. */ 1352 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1353 void sctp_endpoint_free(struct sctp_endpoint *); 1354 void sctp_endpoint_put(struct sctp_endpoint *); 1355 void sctp_endpoint_hold(struct sctp_endpoint *); 1356 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1357 struct sctp_association *sctp_endpoint_lookup_assoc( 1358 const struct sctp_endpoint *ep, 1359 const union sctp_addr *paddr, 1360 struct sctp_transport **); 1361 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1362 const union sctp_addr *paddr); 1363 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1364 struct net *, const union sctp_addr *); 1365 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1366 const union sctp_addr *paddr); 1367 1368 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1369 const struct sctp_association *asoc, 1370 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1371 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1372 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1373 const union sctp_addr *peer, 1374 struct sctp_init_chunk *init, gfp_t gfp); 1375 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1376 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1377 1378 struct sctp_inithdr_host { 1379 __u32 init_tag; 1380 __u32 a_rwnd; 1381 __u16 num_outbound_streams; 1382 __u16 num_inbound_streams; 1383 __u32 initial_tsn; 1384 }; 1385 1386 struct sctp_stream_priorities { 1387 /* List of priorities scheduled */ 1388 struct list_head prio_sched; 1389 /* List of streams scheduled */ 1390 struct list_head active; 1391 /* The next stream stream in line */ 1392 struct sctp_stream_out_ext *next; 1393 __u16 prio; 1394 }; 1395 1396 struct sctp_stream_out_ext { 1397 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1398 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1399 struct list_head outq; /* chunks enqueued by this stream */ 1400 union { 1401 struct { 1402 /* Scheduled streams list */ 1403 struct list_head prio_list; 1404 struct sctp_stream_priorities *prio_head; 1405 }; 1406 /* Fields used by RR scheduler */ 1407 struct { 1408 struct list_head rr_list; 1409 }; 1410 }; 1411 }; 1412 1413 struct sctp_stream_out { 1414 union { 1415 __u32 mid; 1416 __u16 ssn; 1417 }; 1418 __u32 mid_uo; 1419 struct sctp_stream_out_ext *ext; 1420 __u8 state; 1421 }; 1422 1423 struct sctp_stream_in { 1424 union { 1425 __u32 mid; 1426 __u16 ssn; 1427 }; 1428 __u32 mid_uo; 1429 __u32 fsn; 1430 __u32 fsn_uo; 1431 char pd_mode; 1432 char pd_mode_uo; 1433 }; 1434 1435 struct sctp_stream { 1436 struct sctp_stream_out *out; 1437 struct sctp_stream_in *in; 1438 __u16 outcnt; 1439 __u16 incnt; 1440 /* Current stream being sent, if any */ 1441 struct sctp_stream_out *out_curr; 1442 union { 1443 /* Fields used by priority scheduler */ 1444 struct { 1445 /* List of priorities scheduled */ 1446 struct list_head prio_list; 1447 }; 1448 /* Fields used by RR scheduler */ 1449 struct { 1450 /* List of streams scheduled */ 1451 struct list_head rr_list; 1452 /* The next stream stream in line */ 1453 struct sctp_stream_out_ext *rr_next; 1454 }; 1455 }; 1456 struct sctp_stream_interleave *si; 1457 }; 1458 1459 #define SCTP_STREAM_CLOSED 0x00 1460 #define SCTP_STREAM_OPEN 0x01 1461 1462 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1463 { 1464 return stream->si->data_chunk_len; 1465 } 1466 1467 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1468 { 1469 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1470 } 1471 1472 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1473 { 1474 return stream->si->ftsn_chunk_len; 1475 } 1476 1477 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1478 { 1479 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1480 } 1481 1482 /* SCTP_GET_ASSOC_STATS counters */ 1483 struct sctp_priv_assoc_stats { 1484 /* Maximum observed rto in the association during subsequent 1485 * observations. Value is set to 0 if no RTO measurement took place 1486 * The transport where the max_rto was observed is returned in 1487 * obs_rto_ipaddr 1488 */ 1489 struct sockaddr_storage obs_rto_ipaddr; 1490 __u64 max_obs_rto; 1491 /* Total In and Out SACKs received and sent */ 1492 __u64 isacks; 1493 __u64 osacks; 1494 /* Total In and Out packets received and sent */ 1495 __u64 opackets; 1496 __u64 ipackets; 1497 /* Total retransmitted chunks */ 1498 __u64 rtxchunks; 1499 /* TSN received > next expected */ 1500 __u64 outofseqtsns; 1501 /* Duplicate Chunks received */ 1502 __u64 idupchunks; 1503 /* Gap Ack Blocks received */ 1504 __u64 gapcnt; 1505 /* Unordered data chunks sent and received */ 1506 __u64 ouodchunks; 1507 __u64 iuodchunks; 1508 /* Ordered data chunks sent and received */ 1509 __u64 oodchunks; 1510 __u64 iodchunks; 1511 /* Control chunks sent and received */ 1512 __u64 octrlchunks; 1513 __u64 ictrlchunks; 1514 }; 1515 1516 /* RFC2960 1517 * 1518 * 12. Recommended Transmission Control Block (TCB) Parameters 1519 * 1520 * This section details a recommended set of parameters that should 1521 * be contained within the TCB for an implementation. This section is 1522 * for illustrative purposes and should not be deemed as requirements 1523 * on an implementation or as an exhaustive list of all parameters 1524 * inside an SCTP TCB. Each implementation may need its own additional 1525 * parameters for optimization. 1526 */ 1527 1528 1529 /* Here we have information about each individual association. */ 1530 struct sctp_association { 1531 1532 /* A base structure common to endpoint and association. 1533 * In this context, it represents the associations's view 1534 * of the local endpoint of the association. 1535 */ 1536 struct sctp_ep_common base; 1537 1538 /* Associations on the same socket. */ 1539 struct list_head asocs; 1540 1541 /* association id. */ 1542 sctp_assoc_t assoc_id; 1543 1544 /* This is our parent endpoint. */ 1545 struct sctp_endpoint *ep; 1546 1547 /* These are those association elements needed in the cookie. */ 1548 struct sctp_cookie c; 1549 1550 /* This is all information about our peer. */ 1551 struct { 1552 /* transport_addr_list 1553 * 1554 * Peer : A list of SCTP transport addresses that the 1555 * Transport : peer is bound to. This information is derived 1556 * Address : from the INIT or INIT ACK and is used to 1557 * List : associate an inbound packet with a given 1558 * : association. Normally this information is 1559 * : hashed or keyed for quick lookup and access 1560 * : of the TCB. 1561 * : The list is also initialized with the list 1562 * : of addresses passed with the sctp_connectx() 1563 * : call. 1564 * 1565 * It is a list of SCTP_transport's. 1566 */ 1567 struct list_head transport_addr_list; 1568 1569 /* rwnd 1570 * 1571 * Peer Rwnd : Current calculated value of the peer's rwnd. 1572 */ 1573 __u32 rwnd; 1574 1575 /* transport_count 1576 * 1577 * Peer : A count of the number of peer addresses 1578 * Transport : in the Peer Transport Address List. 1579 * Address : 1580 * Count : 1581 */ 1582 __u16 transport_count; 1583 1584 /* port 1585 * The transport layer port number. 1586 */ 1587 __u16 port; 1588 1589 /* primary_path 1590 * 1591 * Primary : This is the current primary destination 1592 * Path : transport address of the peer endpoint. It 1593 * : may also specify a source transport address 1594 * : on this endpoint. 1595 * 1596 * All of these paths live on transport_addr_list. 1597 * 1598 * At the bakeoffs, we discovered that the intent of 1599 * primaryPath is that it only changes when the ULP 1600 * asks to have it changed. We add the activePath to 1601 * designate the connection we are currently using to 1602 * transmit new data and most control chunks. 1603 */ 1604 struct sctp_transport *primary_path; 1605 1606 /* Cache the primary path address here, when we 1607 * need a an address for msg_name. 1608 */ 1609 union sctp_addr primary_addr; 1610 1611 /* active_path 1612 * The path that we are currently using to 1613 * transmit new data and most control chunks. 1614 */ 1615 struct sctp_transport *active_path; 1616 1617 /* retran_path 1618 * 1619 * RFC2960 6.4 Multi-homed SCTP Endpoints 1620 * ... 1621 * Furthermore, when its peer is multi-homed, an 1622 * endpoint SHOULD try to retransmit a chunk to an 1623 * active destination transport address that is 1624 * different from the last destination address to 1625 * which the DATA chunk was sent. 1626 */ 1627 struct sctp_transport *retran_path; 1628 1629 /* Pointer to last transport I have sent on. */ 1630 struct sctp_transport *last_sent_to; 1631 1632 /* This is the last transport I have received DATA on. */ 1633 struct sctp_transport *last_data_from; 1634 1635 /* 1636 * Mapping An array of bits or bytes indicating which out of 1637 * Array order TSN's have been received (relative to the 1638 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1639 * order packets have been received, this array 1640 * will be set to all zero. This structure may be 1641 * in the form of a circular buffer or bit array. 1642 * 1643 * Last Rcvd : This is the last TSN received in 1644 * TSN : sequence. This value is set initially by 1645 * : taking the peer's Initial TSN, received in 1646 * : the INIT or INIT ACK chunk, and subtracting 1647 * : one from it. 1648 * 1649 * Throughout most of the specification this is called the 1650 * "Cumulative TSN ACK Point". In this case, we 1651 * ignore the advice in 12.2 in favour of the term 1652 * used in the bulk of the text. This value is hidden 1653 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1654 */ 1655 struct sctp_tsnmap tsn_map; 1656 1657 /* This mask is used to disable sending the ASCONF chunk 1658 * with specified parameter to peer. 1659 */ 1660 __be16 addip_disabled_mask; 1661 1662 /* These are capabilities which our peer advertised. */ 1663 __u8 ecn_capable:1, /* Can peer do ECN? */ 1664 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1665 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1666 hostname_address:1, /* Peer understands DNS addresses? */ 1667 asconf_capable:1, /* Does peer support ADDIP? */ 1668 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1669 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1670 auth_capable:1; /* Is peer doing SCTP-AUTH? */ 1671 1672 /* sack_needed : This flag indicates if the next received 1673 * : packet is to be responded to with a 1674 * : SACK. This is initialized to 0. When a packet 1675 * : is received sack_cnt is incremented. If this value 1676 * : reaches 2 or more, a SACK is sent and the 1677 * : value is reset to 0. Note: This is used only 1678 * : when no DATA chunks are received out of 1679 * : order. When DATA chunks are out of order, 1680 * : SACK's are not delayed (see Section 6). 1681 */ 1682 __u8 sack_needed:1, /* Do we need to sack the peer? */ 1683 sack_generation:1, 1684 zero_window_announced:1; 1685 __u32 sack_cnt; 1686 1687 __u32 adaptation_ind; /* Adaptation Code point. */ 1688 1689 struct sctp_inithdr_host i; 1690 void *cookie; 1691 int cookie_len; 1692 1693 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1694 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1695 * Initial TSN Value minus 1 1696 */ 1697 __u32 addip_serial; 1698 1699 /* SCTP-AUTH: We need to know pears random number, hmac list 1700 * and authenticated chunk list. All that is part of the 1701 * cookie and these are just pointers to those locations 1702 */ 1703 struct sctp_random_param *peer_random; 1704 struct sctp_chunks_param *peer_chunks; 1705 struct sctp_hmac_algo_param *peer_hmacs; 1706 } peer; 1707 1708 /* State : A state variable indicating what state the 1709 * : association is in, i.e. COOKIE-WAIT, 1710 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1711 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1712 * 1713 * Note: No "CLOSED" state is illustrated since if a 1714 * association is "CLOSED" its TCB SHOULD be removed. 1715 * 1716 * In this implementation we DO have a CLOSED 1717 * state which is used during initiation and shutdown. 1718 * 1719 * State takes values from SCTP_STATE_*. 1720 */ 1721 enum sctp_state state; 1722 1723 /* Overall : The overall association error count. 1724 * Error Count : [Clear this any time I get something.] 1725 */ 1726 int overall_error_count; 1727 1728 /* The cookie life I award for any cookie. */ 1729 ktime_t cookie_life; 1730 1731 /* These are the association's initial, max, and min RTO values. 1732 * These values will be initialized by system defaults, but can 1733 * be modified via the SCTP_RTOINFO socket option. 1734 */ 1735 unsigned long rto_initial; 1736 unsigned long rto_max; 1737 unsigned long rto_min; 1738 1739 /* Maximum number of new data packets that can be sent in a burst. */ 1740 int max_burst; 1741 1742 /* This is the max_retrans value for the association. This value will 1743 * be initialized initialized from system defaults, but can be 1744 * modified by the SCTP_ASSOCINFO socket option. 1745 */ 1746 int max_retrans; 1747 1748 /* This is the partially failed retrans value for the transport 1749 * and will be initialized from the assocs value. This can be 1750 * changed using the SCTP_PEER_ADDR_THLDS socket option 1751 */ 1752 int pf_retrans; 1753 1754 /* Maximum number of times the endpoint will retransmit INIT */ 1755 __u16 max_init_attempts; 1756 1757 /* How many times have we resent an INIT? */ 1758 __u16 init_retries; 1759 1760 /* The largest timeout or RTO value to use in attempting an INIT */ 1761 unsigned long max_init_timeo; 1762 1763 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1764 * the destination address every heartbeat interval. This value 1765 * will be inherited by all new transports. 1766 */ 1767 unsigned long hbinterval; 1768 1769 /* This is the max_retrans value for new transports in the 1770 * association. 1771 */ 1772 __u16 pathmaxrxt; 1773 1774 /* Flag that path mtu update is pending */ 1775 __u8 pmtu_pending; 1776 1777 /* Association : The smallest PMTU discovered for all of the 1778 * PMTU : peer's transport addresses. 1779 */ 1780 __u32 pathmtu; 1781 1782 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1783 __u32 param_flags; 1784 1785 __u32 sackfreq; 1786 /* SACK delay timeout */ 1787 unsigned long sackdelay; 1788 1789 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1790 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1791 1792 /* Transport to which SHUTDOWN chunk was last sent. */ 1793 struct sctp_transport *shutdown_last_sent_to; 1794 1795 /* Transport to which INIT chunk was last sent. */ 1796 struct sctp_transport *init_last_sent_to; 1797 1798 /* How many times have we resent a SHUTDOWN */ 1799 int shutdown_retries; 1800 1801 /* Next TSN : The next TSN number to be assigned to a new 1802 * : DATA chunk. This is sent in the INIT or INIT 1803 * : ACK chunk to the peer and incremented each 1804 * : time a DATA chunk is assigned a TSN 1805 * : (normally just prior to transmit or during 1806 * : fragmentation). 1807 */ 1808 __u32 next_tsn; 1809 1810 /* 1811 * Last Rcvd : This is the last TSN received in sequence. This value 1812 * TSN : is set initially by taking the peer's Initial TSN, 1813 * : received in the INIT or INIT ACK chunk, and 1814 * : subtracting one from it. 1815 * 1816 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1817 */ 1818 1819 __u32 ctsn_ack_point; 1820 1821 /* PR-SCTP Advanced.Peer.Ack.Point */ 1822 __u32 adv_peer_ack_point; 1823 1824 /* Highest TSN that is acknowledged by incoming SACKs. */ 1825 __u32 highest_sacked; 1826 1827 /* TSN marking the fast recovery exit point */ 1828 __u32 fast_recovery_exit; 1829 1830 /* Flag to track the current fast recovery state */ 1831 __u8 fast_recovery; 1832 1833 /* The number of unacknowledged data chunks. Reported through 1834 * the SCTP_STATUS sockopt. 1835 */ 1836 __u16 unack_data; 1837 1838 /* The total number of data chunks that we've had to retransmit 1839 * as the result of a T3 timer expiration 1840 */ 1841 __u32 rtx_data_chunks; 1842 1843 /* This is the association's receive buffer space. This value is used 1844 * to set a_rwnd field in an INIT or a SACK chunk. 1845 */ 1846 __u32 rwnd; 1847 1848 /* This is the last advertised value of rwnd over a SACK chunk. */ 1849 __u32 a_rwnd; 1850 1851 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1852 * to slop over a maximum of the association's frag_point. 1853 */ 1854 __u32 rwnd_over; 1855 1856 /* Keeps treack of rwnd pressure. This happens when we have 1857 * a window, but not recevie buffer (i.e small packets). This one 1858 * is releases slowly (1 PMTU at a time ). 1859 */ 1860 __u32 rwnd_press; 1861 1862 /* This is the sndbuf size in use for the association. 1863 * This corresponds to the sndbuf size for the association, 1864 * as specified in the sk->sndbuf. 1865 */ 1866 int sndbuf_used; 1867 1868 /* This is the amount of memory that this association has allocated 1869 * in the receive path at any given time. 1870 */ 1871 atomic_t rmem_alloc; 1872 1873 /* This is the wait queue head for send requests waiting on 1874 * the association sndbuf space. 1875 */ 1876 wait_queue_head_t wait; 1877 1878 /* The message size at which SCTP fragmentation will occur. */ 1879 __u32 frag_point; 1880 __u32 user_frag; 1881 1882 /* Counter used to count INIT errors. */ 1883 int init_err_counter; 1884 1885 /* Count the number of INIT cycles (for doubling timeout). */ 1886 int init_cycle; 1887 1888 /* Default send parameters. */ 1889 __u16 default_stream; 1890 __u16 default_flags; 1891 __u32 default_ppid; 1892 __u32 default_context; 1893 __u32 default_timetolive; 1894 1895 /* Default receive parameters */ 1896 __u32 default_rcv_context; 1897 1898 /* Stream arrays */ 1899 struct sctp_stream stream; 1900 1901 /* All outbound chunks go through this structure. */ 1902 struct sctp_outq outqueue; 1903 1904 /* A smart pipe that will handle reordering and fragmentation, 1905 * as well as handle passing events up to the ULP. 1906 */ 1907 struct sctp_ulpq ulpq; 1908 1909 /* Last TSN that caused an ECNE Chunk to be sent. */ 1910 __u32 last_ecne_tsn; 1911 1912 /* Last TSN that caused a CWR Chunk to be sent. */ 1913 __u32 last_cwr_tsn; 1914 1915 /* How many duplicated TSNs have we seen? */ 1916 int numduptsns; 1917 1918 /* These are to support 1919 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1920 * and Enforcement of Flow and Message Limits" 1921 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1922 * or "ADDIP" for short. 1923 */ 1924 1925 1926 1927 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1928 * 1929 * R1) One and only one ASCONF Chunk MAY be in transit and 1930 * unacknowledged at any one time. If a sender, after sending 1931 * an ASCONF chunk, decides it needs to transfer another 1932 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1933 * returns from the previous ASCONF Chunk before sending a 1934 * subsequent ASCONF. Note this restriction binds each side, 1935 * so at any time two ASCONF may be in-transit on any given 1936 * association (one sent from each endpoint). 1937 * 1938 * [This is our one-and-only-one ASCONF in flight. If we do 1939 * not have an ASCONF in flight, this is NULL.] 1940 */ 1941 struct sctp_chunk *addip_last_asconf; 1942 1943 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1944 * 1945 * This is needed to implement itmes E1 - E4 of the updated 1946 * spec. Here is the justification: 1947 * 1948 * Since the peer may bundle multiple ASCONF chunks toward us, 1949 * we now need the ability to cache multiple ACKs. The section 1950 * describes in detail how they are cached and cleaned up. 1951 */ 1952 struct list_head asconf_ack_list; 1953 1954 /* These ASCONF chunks are waiting to be sent. 1955 * 1956 * These chunaks can't be pushed to outqueue until receiving 1957 * ASCONF_ACK for the previous ASCONF indicated by 1958 * addip_last_asconf, so as to guarantee that only one ASCONF 1959 * is in flight at any time. 1960 * 1961 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1962 * 1963 * In defining the ASCONF Chunk transfer procedures, it is 1964 * essential that these transfers MUST NOT cause congestion 1965 * within the network. To achieve this, we place these 1966 * restrictions on the transfer of ASCONF Chunks: 1967 * 1968 * R1) One and only one ASCONF Chunk MAY be in transit and 1969 * unacknowledged at any one time. If a sender, after sending 1970 * an ASCONF chunk, decides it needs to transfer another 1971 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1972 * returns from the previous ASCONF Chunk before sending a 1973 * subsequent ASCONF. Note this restriction binds each side, 1974 * so at any time two ASCONF may be in-transit on any given 1975 * association (one sent from each endpoint). 1976 * 1977 * 1978 * [I really think this is EXACTLY the sort of intelligence 1979 * which already resides in sctp_outq. Please move this 1980 * queue and its supporting logic down there. --piggy] 1981 */ 1982 struct list_head addip_chunk_list; 1983 1984 /* ADDIP Section 4.1 ASCONF Chunk Procedures 1985 * 1986 * A2) A serial number should be assigned to the Chunk. The 1987 * serial number SHOULD be a monotonically increasing 1988 * number. The serial number SHOULD be initialized at 1989 * the start of the association to the same value as the 1990 * Initial TSN and every time a new ASCONF chunk is created 1991 * it is incremented by one after assigning the serial number 1992 * to the newly created chunk. 1993 * 1994 * ADDIP 1995 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 1996 * 1997 * Serial Number : 32 bits (unsigned integer) 1998 * 1999 * This value represents a Serial Number for the ASCONF 2000 * Chunk. The valid range of Serial Number is from 0 to 2001 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2002 * after reaching 4294967295. 2003 */ 2004 __u32 addip_serial; 2005 int src_out_of_asoc_ok; 2006 union sctp_addr *asconf_addr_del_pending; 2007 struct sctp_transport *new_transport; 2008 2009 /* SCTP AUTH: list of the endpoint shared keys. These 2010 * keys are provided out of band by the user applicaton 2011 * and can't change during the lifetime of the association 2012 */ 2013 struct list_head endpoint_shared_keys; 2014 2015 /* SCTP AUTH: 2016 * The current generated assocaition shared key (secret) 2017 */ 2018 struct sctp_auth_bytes *asoc_shared_key; 2019 struct sctp_shared_key *shkey; 2020 2021 /* SCTP AUTH: hmac id of the first peer requested algorithm 2022 * that we support. 2023 */ 2024 __u16 default_hmac_id; 2025 2026 __u16 active_key_id; 2027 2028 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2029 temp:1, /* Is it a temporary association? */ 2030 force_delay:1, 2031 intl_enable:1, 2032 prsctp_enable:1, 2033 reconf_enable:1; 2034 2035 __u8 strreset_enable; 2036 __u8 strreset_outstanding; /* request param count on the fly */ 2037 2038 __u32 strreset_outseq; /* Update after receiving response */ 2039 __u32 strreset_inseq; /* Update after receiving request */ 2040 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2041 2042 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2043 2044 struct sctp_priv_assoc_stats stats; 2045 2046 int sent_cnt_removable; 2047 2048 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2049 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2050 }; 2051 2052 2053 /* An eyecatcher for determining if we are really looking at an 2054 * association data structure. 2055 */ 2056 enum { 2057 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2058 }; 2059 2060 /* Recover the outter association structure. */ 2061 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2062 { 2063 struct sctp_association *asoc; 2064 2065 asoc = container_of(base, struct sctp_association, base); 2066 return asoc; 2067 } 2068 2069 /* These are function signatures for manipulating associations. */ 2070 2071 2072 struct sctp_association * 2073 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2074 enum sctp_scope scope, gfp_t gfp); 2075 void sctp_association_free(struct sctp_association *); 2076 void sctp_association_put(struct sctp_association *); 2077 void sctp_association_hold(struct sctp_association *); 2078 2079 struct sctp_transport *sctp_assoc_choose_alter_transport( 2080 struct sctp_association *, struct sctp_transport *); 2081 void sctp_assoc_update_retran_path(struct sctp_association *); 2082 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2083 const union sctp_addr *); 2084 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2085 const union sctp_addr *laddr); 2086 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2087 const union sctp_addr *address, 2088 const gfp_t gfp, 2089 const int peer_state); 2090 void sctp_assoc_del_peer(struct sctp_association *asoc, 2091 const union sctp_addr *addr); 2092 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2093 struct sctp_transport *peer); 2094 void sctp_assoc_control_transport(struct sctp_association *asoc, 2095 struct sctp_transport *transport, 2096 enum sctp_transport_cmd command, 2097 sctp_sn_error_t error); 2098 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2099 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2100 int sctp_assoc_update(struct sctp_association *old, 2101 struct sctp_association *new); 2102 2103 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2104 2105 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2106 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2107 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2108 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2109 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2110 void sctp_assoc_set_primary(struct sctp_association *, 2111 struct sctp_transport *); 2112 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2113 struct sctp_transport *); 2114 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2115 enum sctp_scope scope, gfp_t gfp); 2116 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2117 struct sctp_cookie*, 2118 gfp_t gfp); 2119 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2120 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2121 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2122 const struct sctp_association *asoc, 2123 __be32 serial); 2124 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2125 2126 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2127 const union sctp_addr *ss2); 2128 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2129 2130 /* A convenience structure to parse out SCTP specific CMSGs. */ 2131 struct sctp_cmsgs { 2132 struct sctp_initmsg *init; 2133 struct sctp_sndrcvinfo *srinfo; 2134 struct sctp_sndinfo *sinfo; 2135 struct sctp_prinfo *prinfo; 2136 struct sctp_authinfo *authinfo; 2137 struct msghdr *addrs_msg; 2138 }; 2139 2140 /* Structure for tracking memory objects */ 2141 struct sctp_dbg_objcnt_entry { 2142 char *label; 2143 atomic_t *counter; 2144 }; 2145 2146 #endif /* __sctp_structs_h__ */ 2147